1. Field of the Invention
The present invention relates to an ultrasound detection device, and more particularly, to a scanning ultrasound device using two-wave mixing in photorefractive crystal interferometry for non-destructive and non-contact inspection.
2. Description of Related Art
The inspection for defects in material structures is always a critical issue for monitoring and controlling quality in the manufacturing industry. In the conventional destructive inspection for defects, the whole package of a tested sample (e.g. an IC for inspection) is destructively taken apart. For example, in the inspection for insufficient solder or short circuit problem in an integrated circuit (IC), the packaged IC has to be dissolved with a corrosive solution, and then, pins of the IC are inspected with a microscope. However, this inspection process is complex, and is disadvantageous to real-time monitor quality assurance on-line.
Recently, the industry has developed a non-destructive inspection system for monitoring and controlling quality. The process for the non-destructive inspection primarily uses X-rays, an ultrasound probe head as well as an ultrasound optical excitation and detection, etc. Especially, the ultrasound optical excitation and detection has become the main stream for developing the non-destructive inspection because of advantages of remote excitation and detection as well as real-time inspection.
A Two-Wave Mixing in PhotoRefractive Crystal interferometer (TWM in PRC) is considered as the core part of the contemporary ultrasound optical detection system. To apply TWM in PRC to the non-destructive inspection by ultrasound in practice, scanning technology has to be adopted. The conventional solution is to displace or re-locate the whole interferometer system to achieve a scanning function. However, additional mechanism is necessary for this conventional solution, and thus, it complicates the inspection system and increases cost in volume production.
Therefore, it is desirable to provide an optical scanning ultrasound device by TWM in PRC to mitigate and/or obviate the aforementioned problems.